• Title/Summary/Keyword: ground property

Search Result 474, Processing Time 0.037 seconds

Thermal Response Property of Grout Materials from In-situ Test and Temperature Variation of Ground Heat Exchanger (그라우트 재료별 열응답 특성 및 열교환기 운전온도 변화)

  • Kim, Kap-Duk;Lee, Soung-Ju;Yun, Yeo-Sang
    • Proceedings of the SAREK Conference
    • /
    • 2008.06a
    • /
    • pp.769-775
    • /
    • 2008
  • The objective of this report is to determine the difference of thermal response that grouted two different materials, and compare the simulation result of the length of total ground heat exchanger length that using the ground thermal conductivity. And also to know heat exchange variation of ground heat exchanger temperature that measured with various test depth. The result shows that the test hole grouted with water permeable material got better thermal response than grouted with water impermeable material. However, with consideration of ingnore for the initial 12 hour data, the test hole grouted with impermeable material has larger thermal conductivity than the other. By former thermal conductivity, simulated data by engineering program shows only 3.4% difference or less. This result shows that ground thermal conductivity is not the main variables for the design program of ground heat exchanger. At the cooling or heating mode, base on the depth of -150m, the ground heat exchanger has best temperature at $-90{\sim}-60m$ and than getting worse because of entering water heat exchanged with leaving water in the same hole.

  • PDF

A Study on Application for Custody in CIETAC Arbitration Rule (중국 CIETAC 중재규칙상의 보전신청에 관한 연구)

  • 윤진기
    • Journal of Arbitration Studies
    • /
    • v.13 no.2
    • /
    • pp.47-68
    • /
    • 2004
  • The problems on application for custody in CIETAC Arbitration Rule are examined in this paper. First, The issue of jurisdiction for application for custody is arisen from the expansion of material jurisdiction of CIETAC. Until 1998, CIETAC had a jurisdiction only for the cases involving foreigners, but now, it has a jurisdiction not only for the cases involving foreigners but also for domestic cases. In the cases of arbitrating disputes involving foreigners, if the parties concerned apply for the preservation of property, CITEAC shall forward the application to and obtain a ruling from an intermediate people's court in the place where the object of the application resides, or where the property is located. But in the cases of arbitrating domestic disputes, if the parties concerned apply for the preservation of property, CITEAC shall forward the application to and obtain a ruling from an ground-level people's court in the place where the object of the application resides, or where the property is located. Therefore, "People's court" in article 23 of CIETAC Arbitration Rule includes both intermediate people's court and ground-level people's court in its meaning. Second, in the cases that the party concerned submits arbitration to CIETAC, it is not permitted for the party to ask the people's court for custody of property before submitting an arbitration. But there still can be the urgent cases that interests of the party concerned are at stake, and legitimate rights and interests of the party concerned may be damaged beyond remedy, if no application for custody of property is filed immediately. In that cases, even if the party may apply for custody of property with the people's court after submitting an arbitration, it might be too late to preserve property. Therefore, Chinese laws and rules have to be revised so that the party may ask the people's court for custody of property before submitting an arbitration. When revising laws and rules, according to the today's legislation trends, it must be considered that court and arbitration tribunal both have a right to decide the custody of property. When arbitration tribunal decides it, the procedural provisions executing it must be provided. It is also required that China permit to apply preservation of evidence as well as custody of property before submitting an arbitration. It is also strongly recommended that China permit custody of property or preservation of evidence even in the cases that an arbitration is submitted to the arbitration institute which is located in foreign country, not in China.

  • PDF

MIMO Antenna Using Resonance of Ground Planes for 4G Mobile Application

  • Zhao, Xing;Kwon, Kyeol;Choi, Jeahoon
    • Journal of electromagnetic engineering and science
    • /
    • v.13 no.1
    • /
    • pp.51-53
    • /
    • 2013
  • A MIMO antenna using the resonance of ground planes is proposed for 4G mobile application. A resonant mode is generated when the double ground planes (upper and lower) in the mobile terminal are excited as the radiator. By combining the resonant modes contributed from both the antenna element and the ground planes, the proposed MIMO antenna realizes a wideband property over LTE band 13. In addition, an inductive coil is employed to reduce the antenna volume. These approaches not only simplify antenna design but also effectively improve bandwidth and efficiency. The proposed MIMO antenna has an excellent ECC value of below 0.1 because of the nearly orthogonal radiation patterns of the two radiators. Moreover, an additional antenna is adopted to cover WiMAX, WLAN, and Bluetooth services simultaneously in frequency range from 2 GHz to 2.7 GHz.

A Study on the Bearing Capacity characteristics of Stone column by Numerical Analysis (수치해석에 의한 쇄석말뚝의 지지력 특성 고찰)

  • Chun, Byung-Sik;Kim, Baek-Young
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2004.03b
    • /
    • pp.90-99
    • /
    • 2004
  • Stone column is one of the soft ground improvement method, which enhances ground conditions through ground water draining, settlement reducing and bearing capacity increasing complexly by using crushed stone instead of sand in general vertical drain methods. In recent, general construction material, sand is in short of supply, because of the unbalance of demand and supply. Also, the bearing capacity improving effect of stone column method is needed in many cases so the bearing capacity estimation is considered as important point. Nevertheless, adequate estimation methods to predict bearing capacity of stone column considering stone column and improving ground behavior reciprocally is not yet prepared. To contribute this situation, bearing capacity behavior of stone column were simulated as numerically on various property cases of crushed stone and surrounded ground. Through the numerical analysis of simulation results, bearing capacity behavior prediction formula was suggested. This formula was verified by comparing the prediction result with in situ test.

  • PDF

Improvement Effects of Soft Clay Soils Using Quick Lime Piles (생석회 말뚝을 이용한 연약점토지반의 개량효과)

  • Kim, Younghun;Chun, Byungsik
    • Journal of the Korean GEO-environmental Society
    • /
    • v.11 no.5
    • /
    • pp.45-51
    • /
    • 2010
  • This study is to evaluate an application of technology to the soft ground stability using quick lime pile in the field. We investigated properties of Korean quick lime by conducting loading test and theoretical consideration about a principle and property of soft ground improvement by quicklime. According to the test results, it was estimated that quick lime pile method has dehydration effect by absorption of quick lime, consolidation effect by swelling of pile, increasing bearing by strength of pile itself and decreasing sinking effect, etc. A material property of quick lime is favorable for construction and considerable strength. In the case of higher strength is required, using cement as additive would increase material strength.

Effect of Input Soil Properties for Round Robin Test on Ground Response Analysis (지반 응답 해석 Round Robin Test의 입력 지반 물성에 따른 지반 응답 특성 영향 고찰)

  • Kim, Bong-Soo;Lee, Sei-Hyun;Choo, Yun-Wook;Park, Sung-Sik;Kim, Dong-Joon
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2007.09a
    • /
    • pp.305-316
    • /
    • 2007
  • Free field ground motion during earthquake is significantly affected by the local soil conditions and it is essential for the seismic design to perform the site specific ground response analysis. So, Round Robin Test (RRT) on ground response analysis was performed for three sites in Korea. A total of 12 teams presented the results of ground response analysis with used input soil properties based on own judgement. In this paper, the results of one dimensional equivalent linear analysis presented by 11 teams were compared to evaluate the effect of input soil properties on ground response analysis. Additionally, 4 influence factors on ground response analysis, that is shear wave velocity of soil layer, nonlinear dynamic deformational characteristics, bedrock depth and bedrock velocity were studied for assumed simple soil conditions.

  • PDF

Parametric Study on Displacement of Earth Retaining Wall by the Bermed Excavation Using Back Analysis (역해석을 통한 소단굴착에 따른 흙막이 벽체변위의 매개변수 연구)

  • Lee, Myoung-Han;Kim, Tae-Hyung
    • Journal of the Korean Geosynthetics Society
    • /
    • v.14 no.4
    • /
    • pp.23-33
    • /
    • 2015
  • Together with the wall stiffness, a berm has the role of deciding the stability of a temporary retaining wall before structure installation after excavation. Especially in case of loose or soft soil excavated ground, the role of berm is very important. In this study, the measurement data obtained from the temporary retaining wall in the bermed excavation site in urban and numerical analysis are used to investigate the effects of berm's dimension (width and slope), excavation depth and ground property on the maximum horizontal displacement of the temporary retaining wall. The measurement data indicated that the wall displacement varied to the berm's width. That is, as the berm width decreased, the wall displacement increased. As a result of numerical analyses, the maximum wall displacement increased as slope increased and berm width decreased. This means that the berm is effectively restrained to the wall displacement. As excavation depth increased, the effect of berm's slope and width increased. In case of the same berm condition, the wall displacement restrained as ground property increased.

Enhancement of Dissolution Properties of Poorly Soluble Drugs (III) -Dissolution Enhancement of Furosemide from Ground Mixtures with Chitin or Chitosan- (난용성 약물의 용출 증가 (제 3 보) -키틴 또는 키토산과의 혼합분쇄물로부터의 푸로세미드의 용출 증가-)

  • Shin, Sang-Chul;Oh, In-Joon;Lee, Kang-Choon;Lee, Yong-Bok;Koh, Ik-Bae
    • Journal of Pharmaceutical Investigation
    • /
    • v.17 no.4
    • /
    • pp.175-181
    • /
    • 1987
  • To increase the dissolution rate of furosemide, chitin and chitosan which are widely occurring biodegradable natural materials were used as drug carriers. The ground mixtures of furosemide with chitin or chitosan were prepared by grinding in a ball mill. The ground mixture showed a faster and more enhanced dissolution rate than the physical mixture or intact furosemide. The crystalline peaks of furosemide disappeared in the ground mixtures indicating the production of amorphous form. The comparison of infrared spectra of the physical mixture and the ground mixture showed an interaction such as association between the functional groups of furosemide and chitin or chitosan in the molecular level. The weight losses in TGA curves showed all the same patterns. However, the endothermic peak due to the fusion of furosemide in DTA curve disappeared in the ground mixture indicating the different thermal property. The dissolution of furosemide from ground mixtures was fast in the order of chitosan and then chitin. The co-grinding technique with chitin or chitosan provided a promising way enhancing the dissolution rate of practically insoluble drug.

  • PDF

Centrifuge Model Experiments on Behaviour Characterisitc in Forced Replacement Method (강제치환 거동특성에 관한 원심모형실험)

  • Lee, Jong-Ho;Park, Byung-Soo;Jeong, Gil-Soo;Yoo, Nam-Jae
    • Journal of Industrial Technology
    • /
    • v.23 no.A
    • /
    • pp.131-137
    • /
    • 2003
  • This thesis is results of centrifuge model experiments to investigate the behavior of replacement method in dredged and reclaimed ground. For experimental works, centrifuge model tests were carried out to investigate the behavior of replacement method in soft clay ground. Basic soil property tests were performed to find mechanical properties of clay soil sampled from the southern coast of Korea which was used for ground material in the centrifuge model tests. Reconstituted clay ground of model was prepared by applying preconsolidation pressure in 1g condition with specially built model container. Centrifuge model tests were carried out under the artificially accelerated gravitational level of 50g. Replacing material of leads having a certain degree of angularity was used and placed until the settlement of embankment of replacing material was reached to the equilibrium state. Vertical displacement of replacing material was monitored during tests. Depth and shape of replacement, especially the slope of penetrated replacing material and water contents of clay ground were measured after finishing tests. Model tests of investigating the stability of embankment after backfilling were also performed to simulate the behavior of the dike treated with replacement and backfilled with sandy material. As a result of centrifuge model test, the behavior of replacement, the mechanism of the replacing material being penetrated into clay ground and depth of replacement were evaluated.

  • PDF

A Study on the Aerodynamic Analysis of Tandem Airfoil under Ground Effect (지면효과를 갖는 직렬 에어포일 주위의 공력 해석에 관한 연구)

  • Im Ye-Hoon;Chang Keun-Shik
    • 한국전산유체공학회:학술대회논문집
    • /
    • 1999.11a
    • /
    • pp.174-180
    • /
    • 1999
  • Aerodynamic characteristics of tandem airfoil under ground effect is investigated numerically. Some numerical results for NACA 6409 tandem airfoil are presented. The numerical results show that as being decreased distance between airfoils, the lift coefficient of leading airfoil is increased and that of trailing airfoil is decreased. Drag coefficient shows opposite property, At the same distance between leading airfoil and trailing airfoil, lower position of trailing airfoil give better tandem airfoil effect.

  • PDF